| Parameter |
Value |
| Designation |
C/1955 L1 (Mrkos) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1955-06-04T03:57:09.207360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:12Z |
| Obs used |
21 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1955-07-14.0000000 |
| e |
0.98921350 |
| q (au) |
0.534369 |
| a (au) |
49.540478 |
| i (deg) |
86.503010 |
| Ω (om, deg) |
48.941547 |
| ω (w, deg) |
32.506239 |
| M (ma, deg) |
0.112598 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.847 + 4.080\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.847 |
| n |
4.080 |
| gf |
1.000 |
| gb |
-0.565 |
| k |
0.800 |
| δ90 |
10.000 |
| Parameter |
Symbol |
Range |
Description |
| Absolute magnitude at 1 AU from Sun and Earth |
H0 |
-5 to 20 |
Intrinsic brightness of the comet |
| Photometric slope parameter |
n |
2 to 6 |
Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor |
gf |
0.8 to 1 |
Degree of forward scattering |
| Backward scattering asymmetry factor |
gb |
-1 to -0.5 |
Degree of backward scattering |
| Partitioning coefficient |
k |
0.8 to 1 |
Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio |
δ90 |
1 to 10 |
Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
14:30:24.76 |
-44:06:59.1 |
HIP 70918 |
15.39 |
| 2026-09-20 12:00 |
14:30:26.29 |
-44:06:56.5 |
HIP 70918 |
15.39 |
| 2026-09-21 00:00 |
14:30:27.84 |
-44:06:54.0 |
HIP 70918 |
15.41 |
| 2026-09-21 12:00 |
14:30:29.40 |
-44:06:51.6 |
HIP 70918 |
15.43 |
| 2026-09-22 00:00 |
14:30:30.97 |
-44:06:49.3 |
HIP 70918 |
15.46 |
| 2026-09-22 12:00 |
14:30:32.55 |
-44:06:47.1 |
HIP 70918 |
15.50 |
| 2026-09-23 00:00 |
14:30:34.14 |
-44:06:45.0 |
HIP 70918 |
15.54 |
| 2026-09-23 12:00 |
14:30:35.75 |
-44:06:43.1 |
HIP 70918 |
15.59 |
| 2026-09-24 00:00 |
14:30:37.36 |
-44:06:41.2 |
HIP 70918 |
15.65 |
| 2026-09-24 12:00 |
14:30:38.99 |
-44:06:39.5 |
HIP 70918 |
15.72 |
| 2026-09-25 00:00 |
14:30:40.63 |
-44:06:37.8 |
HIP 70918 |
15.79 |
| 2026-09-25 12:00 |
14:30:42.27 |
-44:06:36.3 |
HIP 70918 |
15.88 |
| 2026-09-26 00:00 |
14:30:43.93 |
-44:06:34.9 |
HIP 70970 |
15.88 |
| 2026-09-26 12:00 |
14:30:45.60 |
-44:06:33.6 |
HIP 70970 |
15.80 |
| 2026-09-27 00:00 |
14:30:47.28 |
-44:06:32.4 |
HIP 70970 |
15.73 |
| 2026-09-27 12:00 |
14:30:48.97 |
-44:06:31.3 |
HIP 70970 |
15.67 |
| 2026-09-28 00:00 |
14:30:50.67 |
-44:06:30.4 |
HIP 70970 |
15.62 |
| 2026-09-28 12:00 |
14:30:52.38 |
-44:06:29.5 |
HIP 70970 |
15.57 |
| 2026-09-29 00:00 |
14:30:54.10 |
-44:06:28.8 |
HIP 70970 |
15.53 |
| 2026-09-29 12:00 |
14:30:55.83 |
-44:06:28.1 |
HIP 70970 |
15.50 |
| 2026-09-30 00:00 |
14:30:57.57 |
-44:06:27.6 |
HIP 70970 |
15.48 |
| 2026-09-30 12:00 |
14:30:59.32 |
-44:06:27.2 |
HIP 70970 |
15.47 |
| 2026-10-01 00:00 |
14:31:01.08 |
-44:06:26.9 |
HIP 70970 |
15.46 |
| 2026-10-01 12:00 |
14:31:02.84 |
-44:06:26.7 |
HIP 70970 |
15.46 |
| 2026-10-02 00:00 |
14:31:04.62 |
-44:06:26.6 |
HIP 70970 |
15.47 |
| 2026-10-02 12:00 |
14:31:06.41 |
-44:06:26.7 |
HIP 70970 |
15.49 |
| 2026-10-03 00:00 |
14:31:08.20 |
-44:06:26.8 |
HIP 70970 |
15.52 |
| 2026-10-03 12:00 |
14:31:10.01 |
-44:06:27.1 |
HIP 70970 |
15.55 |
| 2026-10-04 00:00 |
14:31:11.82 |
-44:06:27.4 |
HIP 70970 |
15.60 |
| 2026-10-04 12:00 |
14:31:13.64 |
-44:06:27.9 |
HIP 70970 |
15.65 |
| 2026-10-05 00:00 |
14:31:15.47 |
-44:06:28.5 |
HIP 70970 |
15.71 |
| 2026-10-05 12:00 |
14:31:17.31 |
-44:06:29.2 |
HIP 70970 |
15.79 |
| 2026-10-06 00:00 |
14:31:19.16 |
-44:06:30.1 |
HIP 70970 |
15.87 |
| 2026-10-06 12:00 |
14:31:21.02 |
-44:06:31.0 |
HIP 70970 |
15.95 |
| 2026-10-07 00:00 |
14:31:22.88 |
-44:06:32.0 |
HIP 70970 |
16.05 |
| 2026-10-07 12:00 |
14:31:24.75 |
-44:06:33.2 |
HIP 70970 |
16.16 |
| 2026-10-08 00:00 |
14:31:26.63 |
-44:06:34.5 |
HIP 70970 |
16.27 |
| 2026-10-08 12:00 |
14:31:28.52 |
-44:06:35.8 |
HIP 70970 |
16.39 |
| 2026-10-09 00:00 |
14:31:30.42 |
-44:06:37.3 |
HIP 70970 |
16.53 |
| 2026-10-09 12:00 |
14:31:32.32 |
-44:06:38.9 |
HIP 70970 |
16.66 |
| 2026-10-10 00:00 |
14:31:34.23 |
-44:06:40.7 |
HIP 70970 |
16.81 |
| 2026-10-10 12:00 |
14:31:36.15 |
-44:06:42.5 |
HIP 70970 |
16.97 |
| 2026-10-11 00:00 |
14:31:38.07 |
-44:06:44.4 |
HIP 70970 |
17.13 |